Screening by negative chemical ionization mass spectrometry for environmental contamination with toxic residues: Application to human urines.

A screening procedure based on solvent extraction with minimal clean up followed by examination with negative chemical ionization mass spectrometry has been developed for organochlorine residues and related compounds with masses greater than 130 daltons. The procedure has been made quantitative for analysis of pentachlorophenol residues. A limited survey of human urines indicated extensive contamination of the subjects, studied at parts per billion and higher levels, with pentachlorophenol, 2, 4, 5-trichlorophenoxy acetic acid, other polychlorophenoxy acids, and numerous unknown compounds. In an attempt to define the source of the contamination, the screening procedure was applied to samples of environmental substrates. The results suggest the food chain as one significant source of the contamination. A preliminary study of organochlorine compounds in human seminal fluid showed pentachlorophenol and other organochlorine residues in every sample, a result which suggests that this area may merit additional monitoring.